Volume 58, Issue 5

The brown algal genus Acinetospora is characterised by sparsely branched uniseriate filaments, scattered meristematic zones, short laterals (“crampons”) and scattered reproductive organs. The morphology and life history of the generitype A. crinita have been studied repeatedly, and accounts of the species’ highly varied reproductive patterns were assumed to be due to the presence of multiple taxa that were reported under this name. Herein, we attempt to contribute to the taxonomy of the genus by conducting morphological and culture studies on 33 Acinetospora samples collected from Japan. We recognised two Acinetospora species and propose to name them A. filamentosa comb. nov. and A. asiatica sp. nov. These two species are distinguished from A. crinita by the absence of monosporangia and plurilocular acinetosporangia/megasporangia. Acinetospora filamentosa and A. asiatica have similar vegetative morphologies but possess different reproductive patterns. The former forms unilocular sporangia on erect filaments and both unilocular sporangia and plurilocular zoidangia on prostrate filaments, while the latter forms plurilocular zoidangia only on both erect and prostrate filaments. Molecular analyses based on rbc L and cox 1 genes supported independence of these species.

Neosiphonia echinata, a well-known western Atlantic species, is here reported for the first time from Indonesia and this extends its distribution into Southeast Asia. Neosiphonia echinata was collected from Sulawesi, Indonesia as an epiphyte on Kappaphycus alvarezii and growing on ropes in a culture farm. We also collected this species from Florida, USA, and then compared their morphology and molecular data. Neosiphonia echinata is identified by having erect main filaments arising from prostrate filaments, numerous rhizoids cutting off from the proximal end of pericentral cells by a cross wall, four pericentral cells throughout the thallus, ecorticate axes, very long and abundant trichoblasts more than twice forked, abundant adventitious laterals, procarps with four-celled carpogonial branches, and a spiral arrangement of tetrasporangia. Our phylogenetic analyses of rbc L and cox 1 indicate that N. echinata found in Indonesia was very closely related to material from the Western Atlantic Ocean. Neosiphonia echinata may be added as an introduced species to the Indonesian marine flora. The shipping routes western Atlantic-Mediterranean-Indonesia and western Atlantic-Pacific Ocean-Indonesia might be considered as possible pathways of introduction as a consequence of ballast water and hull fouling.

Continued collection of algae around the island of Puerto Rico principally focused on deep and shallow coral reef habitats led to the additional recognition of nine species previously unknown for the flora, including five Rhodophyta: Liagora tsengii , Crouania elisiae , Crouania pumila , Augophyllum wysori , Chrysymenia ventricosa ; one Heterokontophyta (Phaeophyceae): Zonaria tournefortii ; and three Chlorophyta: Bolbocoleon piliferum , Rhipocephalus oblongus , and Udotea caribaea . Kallymenia limminghei as previously reported from Puerto Rico is now recognized to be a distinct entity, Meredithia puchella , and Meredithia? caribaea is also described as a new species.

The first complete checklist of the intertidal and subtidal marine algae (Rhodophyta, Chlorophyta and Ochrophyta) of Nha Trang Bay (Vietnam) is presented. A brief history of the species records in the bay between 1953 and 2010 is documented. A total of 481 macroalgal taxa and their forms have been found, including 275 red (57%), 121 green (25%) and 85 brown (18%) algal taxa. The data, analyzed in terms of time period, revealed shifts in the number of species in most of the taxonomic families. However, the most interesting differences between the time periods occurred in the overall algal species diversity and in the floristic ratios (red: brown: green algae). The collections sampled in 1953–1968 and those in 1982–1987 did not change significantly in either species diversity or floristic composition, but a comparison of the collections from 1953 to 1987 and from 2002 to 2010 revealed substantial differences. In 2002–2010, the absolute and relative numbers of green algal species increased while those of red and brown algal species decreased. Our background data indicate that this change is likely due to increasing seawater pollution caused by dissolved organic and inorganic substances. The increase in the number of green algal species is due primarily to the greater number of species in the Caulerpaceae, Ulvaceae and Cladophoraceae, all families that thrive in polluted water.

The phenolic fingerprint of the leaves of Posidonia oceanica collected from four different Mediterranean Sea regions was determined using a panel of analytical techniques. It was found to be dominated by caffeic tartrates, along with low amounts of coumaric and ferulic tartrates. Chicoric acid (CA) was unambiguously identified as the major phenolic compound, regardless of the sample or collection site. Caftaric acid (CAF) was the second most abundant phenolic, but in much lower average concentrations. These results contrast with most of the previous works, in which CA was not even mentioned. The dramatic influence of extract handling, as well as the importance of choosing the adequate criteria of identity to standards, was demonstrated. These results show the importance of analyzing the crude extract to avoid some of the major pitfalls in determining the phenolic fingerprints. This is the first report to identify and quantify CAF in the Posidoniaceae and to identify CA as the dominant phenolic in Posidonia leaves. The large accumulation of CA in both living (10.12–12.78 mg g -1 dw) and detrital leaves (2.49–12.11 mg g -1 dw) across large geographical scales is noteworthy. The lack of significant concentrations of flavonoids contrasts with other seagrass genera. Importantly, the phenolic signature of P. oceanica shows significant similarities to those of Cymodocea nodosa and Syringodium filiforme , both belonging to the Cymodoceaceae. These results are discussed in terms of metabolic pathways and phylogenetic relationships.

The marine fungus Paradendryphiella arenariae BCC 17999, isolated from Thailand, was investigated for bioactive secondary metabolite production. Large-scale fermentation in liquid medium yielded several known compounds, including tricycloalternarenes 2b (also known as ACTG-toxin D), 3a, 3b, A, H, and 11a, as well as infectopyrone. Tricycloalternarenes 2b and 3b displayed weak cytotoxic activity against the human small-cell lung cancer cell line NCI-H187.

In spring 2014, thousands of green algal balls were washed up at Dee Why Beach, Sydney, New South Wales, Australia. Reports of algal balls are uncommon in marine systems, and mass strandings on beaches are even more rare, sparking both public and scientific interest. We identified the algal masses as Chaetomorpha linum by using light microscopy and DNA sequencing. We characterize the size and composition of the balls from Dee Why Beach and compare them to previous records of marine algal balls. We describe the environmental conditions that could explain their appearance, given the ecophysiology of C. linum .

During a study of the species diversity and distribution of seagrasses from the Andaman and Nicobar Islands, Halophila beccarii was recorded for the first time. This report updates the list of seagrasses for these islands from nine to ten species. Halophila beccarii was observed in an intertidal area of muddy substratum in Haddo Bay. The occurrence of this species is significant because of its new distributional record and because it is reported as a “vulnerable species” in the IUCN Red List. The morphometric characters, biomass of the species and its habitat are described in Haddo Bay.

A recent floristic survey revealed the occurrence of three species of Xylocarpus in the Andaman and Nicobar Islands, India. Of these, Xylocarpus granatum and X. moluccensis are true mangrove species, whereas X. rumphii is a non-mangrove species. All three Xylocarpus species were recorded from the Andaman Islands, but none of them have been recorded from the Nicobar Islands. The key distinguishing characters of X. granatum , X. moluccensis and X. rumphii are described to resolve the nomenclatural ambiguity of Xylocarpus spp. in the Andaman and Nicobar Islands.